The Dell Precision 3470 Mobile Workstation Supports Single Drive Configuration Only. (One M.2 NGFF (2280) or (2230) Solid State Drive) Note: The M.2 (2280) and (2230) Drives each use a unique thermal Plate and cannot be interchanged. The M.2 (2230) Drive uses thermal plate p/n 0NN8TC and the M.2 (2280) Drive uses thermal plate p/n 0WCGJG. The M.2 (2230) Drive uses a adapter bracket p/n 07HMH to accommodate for the larger M.2 (2280) slot. (The M.2 slot supports PCIe NVMe Generation 4.0 x4 and 3.0 x4 Solid State Drives)